Atopic dermatitis is a chronic itchy skin disease that is common in children but may occur at any age. It is also known as eczema or atopic eczema. There is a strong association between food allergy and atopic dermatitis in the age group of young children, and food allergies are often suspected in children with atopic dermatitis.
Atopic dermatitis usually occurs in people who have an atopic tendency. This means they may develop any or all of three closely linked conditions: atopic dermatitis, asthma and hay fever (allergic rhinitis).
A phenomenon of atopic dermatitis occurs as follows. Patches of sensitive skin flare up in a rash in response to certain triggers. These triggers vary from person to person. In the case of infants and young children, the list of common triggers to watch for includes cow's milk and other possible ingredients of infant formula such as wheat or soy. Atopic dermatitis can become a vicious cycle. Something irritates the child skin, making it red and inflamed. It itches, the child scratches it, and the skin becomes more inflamed. The outer protective layer of the skin is lost, and the affected area becomes even more sensitive to irritants and dries out easily. The infant continues to be exposed to whatever it was that triggered these episodes in the first place. The rash develops further and the cycle perpetuates itself.
There is no known single cause for atopic dermatitis. It probably reflects more than one condition. There are many theories regarding the underlying mechanisms. Current research is investigating the role of filaggrin gene mutations, defects in skin cells (keratinocytes), the immune system, skin surface microbes (bacteria, viruses and yeasts), and many other factors.
All skin conditions and skin diseases can affect the general population or the population of persons at risk of allergies or the population of allergic (hence sick) persons.
Such skin conditions and skin diseases, and in particular atopic dermatitis, are of particular importance for infants, babies or children as they have a sensitive skin that undergoes an intense growth and phases of multiplication, rendering it even more susceptible to skin diseases. The population of infants without history of allergies in their family, and who become allergic, is increasing.
Hypoallergenic foodstuff is a type of food which is unlikely to cause allergic reactions. Hypoallergenic foodstuffs have been developed, in particular for infant formulae, because infants and children are becoming increasingly likely to develop allergy in the first months/years of their life.
Hypoallergenic infant formulae are used to help, prevent and treat allergic diseases and particularly food allergies in infants and occasionally in young children. They are generally made without the use of common allergens like wheat, soy and dairy products. They also usually derive from cow's milk, however because of the way their proteins have been broken down, they are well tolerated by most infants.
Hypoallergenic infant formulae generally come in three main varieties: partially hydrolysed, extensively hydrolysed and free amino-acid-based. Hydrolyzed infant formulae have the larger protein chains broken down into shorter, easy to digest proteins, whereas free amino-acid formulae do not include protein chains at all, but rather contain all the basic amino acids. Partially hydrolysed infant formulae differ from extensively hydrolysed infant formulae in that their protein chains can be longer. Hypoallergenic infant formulae have the drawback that their cost is much higher than the cost of regular cow's milk formulae.
However, there is still a need for hypoallergenic infant formulae for the prevention and/or treatment of skin conditions and skin diseases that infant and even young children can develop, among which atopic dermatitis.
Human milk oligosaccharides (HMOs) are, collectively, the third largest solid constituents in human milk, after lactose and fat. HMO usually consists of lactose at the reducing end with a carbohydrate core that often contains a fucose or a sialic acid at the non-reducing end. There are approximately one hundred milk oligosaccharides that have been isolated and characterized, however these represent only a very small portion of the total number remaining to be characterized.
In the past, infant formulae were developed using HMO ingredients, such as fucosylated oligosaccharides, lacto-N-tetraose, lacto-N-neotetraose, or sialylated oligosaccharides, for different purposes.
EP 0 975 235 B1 from Abbott Laboratories describes a synthetic nutritional composition comprising one or more human milk oligosaccharides, wherein the HMOs in the composition are chosen among a group of eight HMOs (3-fucosyllactose, lacto-N-fucopentaose III, lacto-N-fucopentaose II, difucosyllactose, 2′-fucosyllactose, lacto-N-fucopentaose I, lacto-N-neotetraose and lacto-N-fucopentaose V) wherein said composition is intended for cases of normal, healthy infants, children, adults or individuals having specialized needs such as those that accompany certain pathological conditions. This European patent states that, generally speaking, oligosaccharides protect infants from viral and bacterial infections of the respiratory, gastrointestinal and uro-genital tracts. Nothing is mentioned concerning the issue of atopic dermatitis and more generally the prevention and/or treatment of skin disease.
From the foregoing, it may be seen that there is a need for an effective nutritional composition for the prevention of secondary atopic dermatitis or the promotion of skin health, particularly in infants and young children, and which may be conveniently and safely administered.
There is a need for an improvement of skin conditions or skin diseases, such as atopic dermatitis, by a non-drug-based intervention that is compatible with fragile individuals like infants or babies.
There is a need for a long term effect in the reduction of the frequency, occurrence, severity and/or duration of such skin conditions and skin diseases. There is furthermore a need for an effect that becomes measurable “later in life”, especially some years after the intervention.
There is a need for a food intervention to infants, babies and children, targeted at risks of allergy or not, that induces a reduction of allergic manifestations, especially on the skin.
There is a need for such intervention that induces the maintenance or the improvement of skin health.